numerous: Limerick-Clare- Kerry, Cork. Ir. Ó Géaráin, géar = sharp. This name relates to the Uí Fiachrach of Connacht, so the connection with the Munster Guerins is tenuous. There was a Huguenot name Guérin, but this would hardly account for the name in Limerick and Kerry. See also Gaynor. SI & SGG.